DOCSLIB.ORG

Crystallography Is More Than Crystal Structures

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Crystallography Is More Than Crystal Structures editorial IUCrJ Crystallography is more than crystal structures ISSN 2052-2525 Sine Larsen* NEUTRONjSYNCHROTRON Department of Chemistry, University of Copenhagen, Universitetsparken 5, Copenhagen, 2100, Denmark. *Correspon- dence e-mail: [email protected] The triennial IUCr congresses have always been highlights and sources of scientific inspiration in my years as a crystallographer, because not only do they provide the latest results in your own field of interest but they also give an overview of developments of crystallography in all its facets. The 23rd IUCr Congress in Montreal was no exception, Keywords: crystallography; editorial; neutrons; and it was particularly festive as it was held in the International Year of Crystallography. synchrotron radiation. New research results based on experiments performed with neutrons and synchrotron radiation have always constituted an important component of the Congress. The use of neutrons and synchrotron radiation has increased over the years not only as measured by the number of experiments performed but also by the number of different experimental techniques that are employed. The large research infrastructures are ideal places for crystallographic experiments – not only do they provide neutrons and X-rays but also the technical expertise that enables complex experiments with a variety of techniques. The papers submitted to IUCrJ for the neutron and synchrotron science and tech- nology section reflect the scientific developments observed at IUCr Congresses. A new X-ray technique, rotational X-ray tracking (RXT), has been developed by Liang et al. (2014). They used this technique to study the temperature dependence of a colloidal gel formed by small crystalline alumina particles in decanoic acid, and demonstrated the applicability of RXT for investigation of the viscoelastic properties of Newtonian, and non-Newtonian liquids, solids and their phase transitions. The number of experiments using advanced grazing-incidence techniques for the analysis of soft-matter materials has grown hugely in recent years, owing to progress in instrumentation and data analysis. The IUCrJ feature article by Hexemer & Mu¨ller- Buschbaum (2015), Advanced grazing-incidence techniques for modern soft-matter analysis, is therefore timely. In this review the authors describe how advanced grazing- incidence small- and wide-angle X-ray and neutron scattering (GISAXS, GIWAXS, GISANS and GIWANS) can be used to investigate the morphology of soft-matter materials, the overview being illustrated by excellent examples. Method developments have made it possible to characterize complex soft-matter samples in-depth morpholo- gically. The use of focused micro- to nanometer-sized X-ray beams for the GISAXS and GIWAXS experiments has opened up the study of smaller samples as well as samples in a complex sample environment, like GISAXS with a microfluidic cell. Furthermore, a smaller beam enables very local scattering experiments, which makes it feasible to perform structure determinations of inhomogenous samples. Small-angle X-ray and neutron scattering (SAXS and SANS) methods have also attained great popularity in the crystallographic community for studies of all types of materials. A growing research area is protein solution SAXS, which is a source of structural information for proteins that are difficult to crystallize. In another feature article, Beyond simple small-angle X-ray scattering: developments in online techniques and sample environments by Bras, Koizumi & Terrill (2014), an overview is given of the development of experimental facilities for SAXS experiments at synchrotron radiation facilities. Dedicated SAXS/WAXS (wide-angle X-ray scattering) beamlines are present at most synchrotron radiation facilities and the use of the complementary information available from simultaneous measurement of SAXS and WAXS in time-resolved studies is described well. SAXS and WAXS measurements become even more powerful if they are supported by other types of measurements, and a thorough description of technique combinations and sample environments is also given in the paper by Bras et al. (2014). The advances in SAXS are also shown in other sections of IUCrJ, as illustrated by the following examples. In the materials and computation section, the paper Advanced ensemble modelling of flexible macromolecules using X-ray solution scattering by Tria et IUCrJ (2015). 2, 475–476 http://dx.doi.org/10.1107/S2052252515015626 475 editorial al. (2015) describes new developments in the methods for other experiments that depend strongly on the coherence studying unstructured and flexible molecules by SAXS. The properties of the beam. These wishes of the scientists are likely biology and medicine section of IUCrJ contains examples of to be fulfilled when the next generation of light sources the use of SAXS in complex biological systems (Tian et al., becomes operational in the near future. In the paper The 2015). potential of future light sources to explore the structure and Synchrotron radiation has contributed immensely to the function of matter by Edgar Weckert (2015), the author development of structural biology. Therefore, it is worth provides the technical background for the performance of the mentioning the paper by Helliwell & Mitchell (2015) in the new light sources that are under construction in Sweden biology and medicine section. The authors provide both an (MAX IV) and Brazil (SIRIUS) in a comparison with the excellent overview of the present state of instrumentation, performance of free electron laser facilities. The paper also automation and data analysis and an outlook on future gives a good overview of the scientific opportunities in terms developments. of new types of experiments that can benefit from the higher The experiments performed with free electron lasers brightness, the smaller emittance and the coherence of the (FELs) on small crystals of proteins have materialized in a beam. The first of the new generation of light sources, MAX new field ‘serial crystallography’ (Chapman et al., 2011). A IV, starts operating in 2016 and one could expect that this will very informative review covering the first five years of this lead to new technical developments and new scientific results field has been written by Ilme Schlichting (2015). Advanced for publication in IUCrJ. instrumentation has been used for the measurement of serial crystallographic data, but handling of the sparse data obtained from the experiment seems to be equally important; Ayyer et al. (2015) show how use of the appropriate algorithm makes it References possible to generate crystallographic intensities from sparse Ayyer, K., Philipp, H. T., Tate, M. W., Wierman, J. L., Elser, V. & data, a result that may have a great impact on the develop- Gruner, S. M. (2015). IUCrJ, 2, 29–34. ment of synchrotron radiation serial crystallography. Bras, W., Koizumi, S. & Terrill, N. J. (2014). IUCrJ, 1, 478–491. X-ray techniques for innovation in industry is the title of a Chapman, H. N., Fromme, P., Barty, A., White, T. A., Kirian, R. A., Aquila, A., Hunter, M. S., Schulz, J., DePonte, D. P., Weierstall, U., feature article in the neutron and synchrotron section Doak, R. B., Maia, F. R. N. C., Martin, A. V., Schlichting, I., Lomb, authored by Lawniczak-Jablonska & Cutler (2014). This paper L., Coppola, N., Shoeman, R. L., Epp, S. W., Hartmann, R., Rolles, is a source of inspiration for increased collaborations/inter- D., Rudenko, A., Foucar, L., Kimmel, N., Weidenspointner, G., actions between companies and researchers at universities and Holl, P., Liang, M., Barthelmess, M., Caleman, C., Boutet, S., research institutions. The experimental set-up at present Bogan, M. J., Krzywinski, J., Bostedt, C., Bajt, S., Gumprecht, L., Rudek, B., Erk, B., Schmidt, C., Ho¨mke, A., Reich, C., Pietschner, synchrotron facilities provides unique opportunities for the D., Stru¨der, L., Hauser, G., Gorke, H., Ullrich, J., Herrmann, S., characterization of all types of materials by a variety of Schaller, G., Schopper, F., Soltau, H., Ku¨hnel, K., Messerschmidt, techniques: spectroscopy, diffraction, imaging and scattering. M., Bozek, J. D., Hau-Riege, S. P., Frank, M., Hampton, C. Y., In the paper the authors describe how the needs of industry Sierra, R. G., Starodub, D., Williams, G. J., Hajdu, J., Timneanu, N., can be met by synchrotron facilities and how this has been Seibert, M. M., Andreasson, J., Rocker, A., Jo¨nsson, O., Svenda, M., Stern, S., Nass, K., Andritschke, R., Schro¨ter, C., Krasniqi, F., Bott, stimulated by a project supported by the European Union. M., Schmidt, K. E., Wang, X., Grotjohann, I., Holton, J. M., The paper illustrates the present level of industrial colla- Barends, T. R. M., Neutze, R., Marchesini, S., Fromme, R., Schorb, borations and the great potential for enhancing them in the S., Rupp, D., Adolph, M., Gorkhover, T., Andersson, I., Hirsemann, future. H., Potdevin, G., Graafsma, H., Nilsson, B. & Spence, J. C. H. The large neutron and X-ray facilities are serving a wide (2011). Nature, 470, 73–77. Helliwell, J. R. & Mitchell, E. P. (2015). IUCrJ, 2, 283–291. range of scientific communities extremely well. Synchrotron Hexemer, A. & Mu¨ller-Buschbaum, P. (2015). IUCrJ, 2, 106–125. radiation has had a tremendous impact on the characterization Lawniczak-Jablonska, K. & Cutler, J. (2014). IUCrJ, 1, 604–613. of all types of materials from hard to biological and has Liang, M., Harder, R. & Robinson, I. K. (2014). IUCrJ, 1, 172–178. contributed to the development of new materials. Scientists in Schlichting, I. (2015). IUCrJ, 2, 245–255. a broad range of fields are familiar with the use of photons Tian, X., Vestergaard, B., Thorolfsson, M., Yang, Z., Rasmussen, H. B. & Langkilde, A. (2015). IUCrJ, 2, 9–18. generated by third generation storage rings. However, there Tria, G., Mertens, H. D. T., Kachala, M. & Svergun, D. I. (2015). are also some experiments that could benefit if the beam of IUCrJ, 2, 207–217. photons had a higher brightness and smaller emittance, and Weckert, E. (2015). IUCrJ, 2, 230–245. 476 Sine Larsen More than crystal structures IUCrJ (2015). 2, 475–476.
Load more

Recommended publications
  • On Soft Matter
    FASCINATING Research Soft MATTER Hard Work on Soft Matter What do silk blouses, diskettes, and the membranes of living cells have in common? All three are made barked on an unparalleled triumphal between the ordered structure of building blocks.“ And Prof. Helmuth march. Even information, which to- solids and the highly disordered gas. Möhwald, director of the “Interfaces” from soft matter: if individual molecules are observed, they appear disordered, however, on a larger, day frequently tends to be described These are typically supramolecular department at the MPIKG adds, “To as one of the most important raw structures and colloids in liquid me- supramolecular scale, they form ordered structures. Disorder and order interact, thereby affecting the put it in rather simplified terms, soft materials, can only be generated, dia. Particularly complex examples matter is unusual because its struc- properties of the soft material. At the MAX PLANCK INSTITUTES FOR POLYMER RESEARCH stored, and disseminated on a mas- occur in the area of biomaterials,” ture is determined by several weaker sive scale via artificial soft materials. says Prof. Reinhard Lipowsky, direc- forces. For this reason, its properties in Mainz and of COLLOIDS AND INTERFACES in Golm, scientists are focussing on this “soft matter”. Without light-sensitive coatings, tor of the “Theory” Division of the depend very much upon environ- there would be no microchip - and Max Plank Institute of Colloids and mental and production conditions.” nor would there be diskettes, CD- Interfaces in Golm near Potsdam The answers given by the three ROMs, and videotapes, which are all (MPIKG). Prof. Hans Wolfgang scientists are typical in that their made from coated plastics.
    [Show full text]
  • Soft Matter Theory
    Soft Matter Theory K. Kroy Leipzig, 2016∗ Contents I Interacting Many-Body Systems 3 1 Pair interactions and pair correlations 4 2 Packing structure and material behavior 9 3 Ornstein{Zernike integral equation 14 4 Density functional theory 17 5 Applications: mesophase transitions, freezing, screening 23 II Soft-Matter Paradigms 31 6 Principles of hydrodynamics 32 7 Rheology of simple and complex fluids 41 8 Flexible polymers and renormalization 51 9 Semiflexible polymers and elastic singularities 63 ∗The script is not meant to be a substitute for reading proper textbooks nor for dissemina- tion. (See the notes for the introductory course for background information.) Comments and suggestions are highly welcome. 1 \Soft Matter" is one of the fastest growing fields in physics, as illustrated by the APS Council's official endorsement of the new Soft Matter Topical Group (GSOFT) in 2014 with more than four times the quorum, and by the fact that Isaac Newton's chair is now held by a soft matter theorist. It crosses traditional departmental walls and now provides a common focus and unifying perspective for many activities that formerly would have been separated into a variety of disciplines, such as mathematics, physics, biophysics, chemistry, chemical en- gineering, materials science. It brings together scientists, mathematicians and engineers to study materials such as colloids, micelles, biological, and granular matter, but is much less tied to certain materials, technologies, or applications than to the generic and unifying organizing principles governing them. In the widest sense, the field of soft matter comprises all applications of the principles of statistical mechanics to condensed matter that is not dominated by quantum effects.
    [Show full text]
  • D0tc00217h4.Pdf
    Electronic Supplementary Material (ESI) for Journal of Materials Chemistry C. This journal is © The Royal Society of Chemistry 2020 Electronic Supporting Information What is the role of planarity and torsional freedom for aggregation in a -conjugated donor-acceptor model oligomer? Stefan Wedler1, Axel Bourdick2, Stavros Athanasopoulos3, Stephan Gekle2, Fabian Panzer1, Caitlin McDowell4, Thuc-Quyen Nguyen4, Guillermo C. Bazan5, Anna Köhler1,6* 1 Soft Matter Optoelectronics, Experimentalphysik II, University of Bayreuth, Bayreuth 95440, Germany. 2Biofluid Simulation and Modeling, Theoretische Physik VI, Universität Bayreuth, Bayreuth 95440, Germany 3Departamento de Física, Universidad Carlos III de Madrid, Avenida Universidad 30, 28911 Leganés, Madrid, Spain. 4Center for Polymers and Organic Solids, Departments of Chemistry & Biochemistry and Materials, University of California, Santa Barbara 5Departments of Chemistry and Chemical Engineering, National University of Singapore, Singapore, 119077 6Bayreuth Institute of Macromolecular Research (BIMF) and Bavarian Polymer Institute (BPI), University of Bayreuth, 95440 Bayreuth, Germany. *e-mail: [email protected] 1 1 Simulated spectra Figure S1.1: Single molecule TD-DFT simulated absorption spectra at the wB97XD/6-31G** level for the TT and CT molecules. TT absorption at the ground state twisted cis and trans configurations is depicted. Vertical transition energies have been broadened by a Gaussian function with a half-width at half-height of 1500cm-1. Figure S1.2: Simulated average CT aggregate absorption spectrum. The six lowest vertical transition transition energies for CT dimer configurations taken from the MD simulations have been computed with TD-DFT at the wB97XD/6-31G** level. Vertical transition energies have been broadened by a Gaussian function with a half-width at half-height of 1500cm-1.
    [Show full text]
  • Cell Biology Befriends Soft Matter Physics Phase Separation Creates Complex Condensates in Eukaryotic Cells
    technology feature Cell biology befriends soft matter physics Phase separation creates complex condensates in eukaryotic cells. To study these mysterious droplets, many disciplines come together. Vivien Marx n many cartoons, eukaryotic cells have When the right contacts are made, phase a tidy look. A taut membrane surrounds separation occurs. Ia placid, often pastel-hued lake with well-circumscribed organelles such as Methods multitude ribosomes and a few bits and bobs. It’s a In the young condensate field, Amy helpful simplification of the jam-packed Gladfelter of the University of North cytoplasm. In some areas, there’s even more Carolina at Chapel Hill says her lab intense milling about1–4. To get a sense of intertwines molecular-biology-based these milieus, head to the kitchen with approaches, modeling, and in vitro Tony Hyman of the Max Planck Institute reconstitution experiments using simplified of Molecular Cell Biology and Genetics systems. “You can’t build models that have and Christoph Weber and Frank Jülicher of all the parameters that exist in a cell,” she the Max Planck Institute for the Physics of says. But researchers need to consider that Complex Systems, who note5: “For instance, in vitro work or overexpressing proteins when you make vinaigrette and leave it, you will not do complete justice to condensates come back annoyed to find that the oil and in situ. “Anything will phase separate vinegar have demixed into two different in a test tube,” she says, highlighting phases: an oil phase and a vinegar phase.” Just Eukaryotic cells contain mysterious, malleable, experiments in which crowding agents as oil and vinegar can separate into two stable liquid-like condensates in which there is intense such as polyethylene glycol are used to phases, such liquid–liquid phase separation activity.
    [Show full text]
  • Soft Matter Research at Upenn Organize Anisotropic Bullet Shaped Particles Into 1D Chains 2D Hexag- Onal Structures (3)
    Marquee goes here Soft Matter Research at UPenn organize anisotropic bullet shaped particles into 1D chains 2D hexag- onal structures (3). They have also shown that controlling boundary conditions and particle shape can allow the creation of hybrid washers which combine homeotropic and degenerate planar anchoring (4). The washers change their angle with respect to the far-field direction and are capable of trapping spherical colloids, allowing for the construc- tion of multi-shape colloidal assem- blages. These methods can be used to create complex shapes, further in- creasing the number of techniques Background image: An illustration of edge-pinning effect of focal conic domains (FCDs) in smectic-A liquid crystals available to those involved in creat- with nonzero eccentricity on short, circular pillars in a square array, together with surface topography and cross-polarized optical image of four FCDs on each pillar. The arrangement of FCDs is strongly influenced by the height and shape of the ing complex structures. pillars. Image courtesy of Felice Macera, Daniel Beller, Apiradee Honglawan, and Simon Copar. Advanced Materials Cover: This paper demonstrated an epitaxial approach to tailor the size and symmetry of toric focal conic domain (TFCD) arrays over large areas by exploiting 3D confinement and directed growth of Smectic-A liquid The team is actively contributing crystals with variable dimensions much like the FCDs. to the goals of the MRSEC by ex- panding the techniques available At the Materials Research Science The coalition has published sev- for use in the construction of com- & Engineering Center (MRSEC) at eral papers together. They have plex assemblies.
    [Show full text]
  • Thermal Properties of Graphene Under Tensile Stress
    Thermal properties of graphene under tensile stress Carlos P. Herrero and Rafael Ram´ırez Instituto de Ciencia de Materiales de Madrid, Consejo Superior de Investigaciones Cient´ıficas (CSIC), Campus de Cantoblanco, 28049 Madrid, Spain (Dated: June 7, 2018) Thermal properties of graphene display peculiar characteristics associated to the two-dimensional nature of this crystalline membrane. These properties can be changed and tuned in the presence of applied stresses, both tensile and compressive. Here we study graphene monolayers under tensile stress by using path-integral molecular dynamics (PIMD) simulations, which allows one to take into account quantization of vibrational modes and analyze the effect of anharmonicity on physical observables. The influence of the elastic energy due to strain in the crystalline membrane is studied for increasing tensile stress and for rising temperature (thermal expansion). We analyze the inter- nal energy, enthalpy, and specific heat of graphene, and compare the results obtained from PIMD simulations with those given by a harmonic approximation for the vibrational modes. This approx- imation turns out to be precise at low temperatures, and deteriorates as temperature and pressure are increased. At low temperature the specific heat changes as cp ∼ T for stress-free graphene, and 2 evolves to a dependence cp ∼ T as the tensile stress is increased. Structural and thermodynamic properties display nonnegligible quantum effects, even at temperatures higher than 300 K. More- over, differences in the behavior of the in-plane and real areas of graphene are discussed, along with their associated properties. These differences show up clearly in the corresponding compressibility and thermal expansion coefficient.
    [Show full text]
  • Soft Condensed Matter Daan Frenkel
    Physica A 313 (2002) 1–31 www.elsevier.com/locate/physa Soft condensed matter Daan Frenkel FOM Institute for Atomic and Molecular Physics, Kruislaan 407, 1098 SJAmsterdam, The Netherlands Abstract These lectures illustrate some of the concepts of soft-condensed matter physics, taking exam- ples from colloid physics. Many of the theoretical concepts will be illustrated with the results of computer simulations. After a brief introduction describing interactions between colloids, the paper focuses on colloidal phase behavior (in particular, entropic phase transitions), colloidal hydrodynamics and colloidal nucleation. c 2002 Elsevier Science B.V. All rights reserved. PACS: 82.70.Dd; 02.70.Ns; 64.70.Md; 64.60.Qb Keywords: Soft matter; Colloids; Computer simulation 1. Introduction The topic of these lectures is soft condensed matter physics—but not all of it. My aim is to discuss a few examples that illustrate the analogies and di6erences between “soft” and “hard” matter. The choice of the examples is biased by my own experience. Most of the examples that I discuss apply to colloids. In many ways, colloids behave like giant atoms, and quite a bit of the colloid physics can be understood in this way. However, much of the interesting behavior of colloids is related to the fact that they are, in many respects, not like atoms. In this lecture, I shall start from the picture of colloids as oversized atoms or molecules, and then I shall selectively discuss some features of colloids that are di6erent. My presentation of the subject will be a bit strange, because I am a computer simulator, rather than a colloid scientist.
    [Show full text]
  • Soft Matter and Fractional Mathematics: Insights Into Mesoscopic Quantum and Time-Space Structures
    Soft matter and fractional mathematics: insights into mesoscopic quantum and time-space structures Wen Chen∗ Computational Physics Laboratory, Institute of Applied Physics and Computational Mathematics, P.O. Box 8009, Beijing 100088, P. R. China (29 April 2004) Abstract: Recent years have witnessed a great research boom in soft matter physics. By now, most advances, however, are of empirical results or purely mathematical extensions. The major obstacle is lacking of insights into fundamental physical laws underlying fractal mesostructures of soft matter. This study will use fractional mathematics, which consists of fractal, fractional calculus, fractional Brownian motion, and Levy stable distribution, to examine mesoscopic quantum mechanics and time-space structures governing “anomalous” behaviors of soft matter. Our major new results include fractional Planck quantum energy relationship, fractional phonon, and time-space scaling transform. 1. Introduction The physical principles apply on the physical size scale. Einstein's relativity theory has revealed our universe on the large scale and shown a profound link between time and space. But the theory does not hold at the microscopic subatomic level, where quantum mechanics theory prevails. Between the macroscopic and microscopic levels is the mesoscopic level, in which scope lie the functioning elements of soft matter, also known as soft condensed matter or complicated fluids. Among the best-known soft matter are polymers, colloids, emulsions, foams, living organisms, rubber, oil, soil, other porous media, etc. The behaviors of soft matter have long been observed “bizarre” or “anomalous” compared with those of the ideal solid and fluid matter and can not arise from relativistic or quantum properties of elementary molecules [1].
    [Show full text]
  • Soft Matter COMMUNICATION
    View Online Soft Matter Dynamic Article LinksC< Cite this: DOI: 10.1039/c0sm01205j www.rsc.org/softmatter COMMUNICATION Optimized monotonic convex pair potentials stabilize low-coordinated crystals E. Marcotte,a F. H. Stillingerb and S. Torquato*abc Received 26th October 2010, Accepted 13th January 2011 DOI: 10.1039/c0sm01205j We have previously used inverse statistical-mechanical methods to existed that could achieve unusual many-particle ground states, they optimize isotropic pair interactions with multiple extrema to yield would be easier to produce experimentally, albeit under positive low-coordinated crystal classical ground states (e.g., honeycomb and pressure. However, encoding information in monotonic potentials to diamond structures) in d-dimensional Euclidean space Rd.Herewe yield low-coordinated ground-state configurations in Euclidean demonstrate the counterintuitive result that no extrema are required spaces is highly nontrivial. Such potentials must not only avoid close- to produce such low-coordinated classical ground states. Specifi- packed (highly coordinated) competitors but crystal configurations cally, we show that monotonic convex pair potentials can be opti- that are infinitesimally close in structure (very slight deformations of mized to yield classical ground states that are the square and the targeted low-coordinated crystal), which is a great challenge to honeycomb crystals in R2 over a non-zero number density range. achieve theoretically while maintaining the monotonicity properties. In this communication, we use
    [Show full text]
  • Nonlinear Tunneling of Surface Plasmon Polaritons in Periodic Structures Containing Left-Handed Metamaterial Layers
    Hindawi Publishing Corporation Advances in Condensed Matter Physics Volume 2015, Article ID 343864, 5 pages http://dx.doi.org/10.1155/2015/343864 Research Article Nonlinear Tunneling of Surface Plasmon Polaritons in Periodic Structures Containing Left-Handed Metamaterial Layers Munazza Zulfiqar Ali Physics Department, Punjab University, Quaid-i-Azam Campus, Lahore 54590, Pakistan Correspondence should be addressed to Munazza Zulfiqar Ali; [email protected] Received 3 September 2015; Accepted 30 November 2015 Academic Editor: Rosa Lukaszew Copyright © 2015 Munazza Zulfiqar Ali. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The transmission of surface plasmon polaritons through a one-dimensional periodic structure is considered theoretically by using the transfer matrix approach. The periodic structure is assumed to have alternate left-handed metamaterial and dielectric layers. Both transverse electric and transverse magnetic modes of surface plasmon polaritons exist in this structure. It is found that, for nonlinear wave propagation, tunneling structures are formed to transform nontransmitting frequencies into transmitting frequencies and hence transmission bistability is observed. It is further observed that the structure shows sensitivity with respect to the polarization of the electromagnetic field for this phenomenon. 1. Introduction (TE) and transvers magnetic (TM) modes can exist here. The existence and tunneling of SPPs in different type of periodic As soon as metamaterials touched the optical regime, they structures is also being studied [5, 25]. Models are under havestartedtointerferewiththefieldofplasmonics. consideration to transfer these states along specific structures Plasmonics is concerned with the unique properties and [26, 27].
    [Show full text]
  • A Soft Condensed Matter Model for Universal Phenomena
    Southern Illinois University Carbondale OpenSIUC Research Papers Graduate School 2020 A Soft Condensed Matter Model for Universal Phenomena Justin Cassell [email protected] Follow this and additional works at: https://opensiuc.lib.siu.edu/gs_rp Recommended Citation Cassell, Justin. "A Soft Condensed Matter Model for Universal Phenomena." (Jan 2020). This Article is brought to you for free and open access by the Graduate School at OpenSIUC. It has been accepted for inclusion in Research Papers by an authorized administrator of OpenSIUC. For more information, please contact [email protected]. A SOFT CONDENSED MATTER MODEL FOR UNIVERSAL PHENOMENA by Justin Cassell B.S., Saginaw Valley State University, 2012 A Research Paper Submitted in Partial Fulfillment of the Requirements for the Master of Science Department of Physics in the Graduate School Southern Illinois University Carbondale May 2021 RESEARCH PAPER APPROVAL A SOFT CONDENSED MATTER MODEL FOR UNIVERSAL PHENOMENA by Justin Cassell A Research Paper Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Science in the field of Physics Approved by: Dr. Saikat Talapatra, Chair Graduate School Southern Illinois University Carbondale December 18, 2020 TABLE OF CONTENTS CHAPTER PAGE LIST OF FIGURES ........................................................................................................................ ii CHAPTERS CHAPTER 1 – What is Soft Matter? ...................................................................................1 CHAPTER 2
    [Show full text]
  • Activity-Induced Instability of Phonons in 1D Microfluidic Crystals† Cite This: Soft Matter, 2018, 14,945 Alan Cheng Hou Tsang,Ab Michael J
    Soft Matter View Article Online PAPER View Journal | View Issue Activity-induced instability of phonons in 1D microfluidic crystals† Cite this: Soft Matter, 2018, 14,945 Alan Cheng Hou Tsang,ab Michael J. Shelleycd and Eva Kanso *acd One-dimensional crystals of passively-driven particles in microfluidic channels exhibit collective vibrational modes reminiscent of acoustic ‘phonons’. These phonons are induced by the long-range hydrodynamic interactions among the particles and are neutrally stable at the linear level. Here, we analyze the effect of particle activity – self-propulsion – on the emergence and stability of these phonons. We show that the direction of wave propagation in active crystals is sensitive to the intensity of the background flow. We also show that activity couples, at the linear level, transverse waves to the particles’ rotational motion, inducing a new mode of instability that persists in the limit of large background flow, or, equivalently, vanishingly Received 5th July 2017, small activity. We then report a new phenomenon of phonons switching back and forth between two Accepted 28th December 2017 adjacent crystals in both passively-driven and active systems, similar in nature to the wave switching DOI: 10.1039/c7sm01335c observed in quantum mechanics, optical communication, and density stratified fluids. These findings could have implications for the design of commercial microfluidic systems and the self-assembly of passive and rsc.li/soft-matter-journal active micro-particles into one-dimensional structures. 1 Introduction of particles into 1D structures.19,20 In this study, we analytically and computationally analyze the effect of activity on the stabi- The ability to manipulate and organize the collective motion of lity of 1D lattices of particles confined in microfluidic channels droplets and particles in microfluidic channels is relevant to (see Fig.
    [Show full text]